GU sub tank light staying on

First thing to do is to reset it.

Disconnect the battery for about 10 mins and retry.

That happened to mine (4.5 GU) when I didn't use the subtank enough and the fuel got to low. Like a safety switch.

Had same problem with 2.8 GU a few weeks ago. Out bush and couldn't transfer fuel sorta thing.
Fix was to disconnect battery for a minute or so, reconnect and hey presto.

Seems the ECM(pootr) is very voltage sensitive and can react in this fashion. My problem was possibly caused by connecting camper with low/flat batteries to vehicle with engine running, when the alternator was already battling to charge it's own batteries.

Hope your fix is this simple,
Bruce H.

Hi All,

I also would like some advice on this as I had the same issue last week.

It happened to me for the first time. I had recently completely drained the sub tank over to the main tank.

Is it a case of never fully draining the sub tank, and maybe this will stop the problem?

All help greatly appreciated

Thanks

TonyG

G'day Pat,

There are 2 parts to this issue. The other blokes have covered one aspect; the need to disconnect the battery to re-set the system. That should make the light go off and you'll be able to operate the transfer pump. Also, good idea to always keep fuel in the sub-tank, but I wouldn't go so far as to say that you need to manually switch the pump off before all the fuel gets transferred........just make sure you re-fill the sub-tank next time you're at the servo.

The 2nd point (which nobody above has mentioned yet) is "why" does this happen in the first place. The answer to that question is that the transfer pump (apparently) is the only electrical device on the Patrol that earths to the chassis (as opposed to the body). Anyway, be that as it may..........(somebody could dispute that fact and they could well be correct), the thing I have done to avoid the sub-tank light issue, is to install a fairly heavy-gauge cable from the chassis to the body-work/or motor/battery etc. In fact, on my Patrol, I have put the cable from the chassis just near the turbo (where there is a captive nut welded inside; 100mm thread I think), up to the back of the alternator. That cable used to go to the negative post on my second battery, but when I junked the 2nd battery to make room for the oil by-pass set-up, I had to find another well-earthed spot to fit the lug onto.

Hope this helps mate

Roachie

I had haep of prob swith my GU fuel guages - reading only 80% full, 10 minutes after refuelling, guages always wrong etc.

I read somewhere on ExOZ that the body earth set up on the GU is not the best and the fuel gauges are particularly sensitive. I fixed this by fitting an extra earth with heavy guage cable, direct from the battery negative to the firewall. That's fixed all the probs with the fuel guages AND the CD doesn't play up like it used to either! No more "ERROR CODES" on the CD Player.

Bilbo

Gee, you blokes are good. I was towing my CT for the first time when I fuelled up so this may have been a factor. All is good now though.
My auto sparky hooked up an Anderson plubg and an extra earth to the chassis for me last week so hopefully that issue is OK.

Cheers PP

Hi had the same problem some time ago. Had to earth the body and chassis back to the battery. And then earth the fuel tank. Not a problem since.

Cheers